?S about pistons and rods.

on a crankshaft balancer, duh

as for counterweights not needed on a inline 4
see the ends on the cranks? those are counterweights... from the factory
FS-DE crank
23157710522_large.jpg


let me blow it up for you
fig4.jpg


I don't know where you copied that full of s*** information from, but almost all modern engines have counter weights including inline4s

here'a a pic of 2 Honda cranks.
DCP00849highlighted.jpg

no counterweights? (uhm)
get your information from more than one place next time you do a search.
 
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i know our car do have counter weight...i quoted this somewhere. And I guess the reason he said counterweight is no needed because there will me no inertia, like LW flywheel, or the counter weight serve to balance the crank itself. Now explain how the **** you balance dynamically in a balancer with everything attached, oil pump? balance rpm? you balance the engine by turning it witout oiling? and HOW THE **** you mesure the imbalance of the assembly with everything attached? Do you know about secondary harmonic? You ever seen how a crank balancer works? Do you know how it works? Have you ever used a crank balancer and balance it yourself? Come on gimme more info mr knowledge.
 
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HAHAHA, oh dude you never fail to make me laugh.

You don't assemble the engine and then spin it to redline on a balancer. You weigh each cylinder's components (rod, piston, wrist pin) and use bob weights of the measured assembly's weight to hang from the crank. Then you run the balancer and find the imbalance.

That is "HOW THE ****" you dynamically balance it.
 
lol... ppl are getting angry in here...
hehe... i say as long as it runs and hauls a$$ we're good to go :)
i never had a engine put together yet by a machine shop... but i would guess that they balance the sh!t before giving it back... i don't think they want you to come back and blame them for a messed up job

as for the OP's original question... just head over to protegegarage and pick up a set of K1's and Wiesco's or Pauters And Aries put that sh!t in and call it a day
 
low_psi said:
HAHAHA, oh dude you never fail to make me laugh.

You don't assemble the engine and then spin it to redline on a balancer. You weigh each cylinder's components (rod, piston, wrist pin) and use bob weights of the measured assembly's weight to hang from the crank. Then you run the balancer and find the imbalance.

That is "HOW THE ****" you dynamically balance it.
Click to expand...

you kidding me right? bob weight for a inline 4? you actually put the total mass of piston rod bearing wristpin assem and attach to the crank? thats not the way you balance a inline 4 motor, the top of rod is moving vertifcally and the bottom of the rod is turning around... as piston is goin up and down in a motor and not turing around... the real balance is done by scaling the weight of reciprocating mass and balance the rotating part. Call AMS performance and ask them how to balance their engine, get informed. The procedure is written on crank balancer user manual.

BTW people should stop laughin and post some useful information to argue.
 
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XoX1de said:
you kidding me right? bob weight for a inline 4? you actually put the total mass of piston rod bearing wristpin assem and attach to the crank? thats not the way you balance a inline 4 motor, the top of rod is moving vertifcally and the bottom of the rod is turning around... as piston is goin up and down in a motor and not turing around... the real balance is done by scaling the weight of reciprocating mass and balance the rotating part. Call AMS performance and ask them how to balance their engine, get informed. The procedure is written on crank balancer user manual.

BTW people should stop laughin and post some useful information to argue.
Click to expand...


XoX1de, you are one of the very few on MazdaForums that actually have engine building knowledge that I have seen. You are correct in everything that you have stated in this thread. The only thing that I must add to what you have said is this. For those of you looking to cut corners due to finacial status YOU CANNOT AFFORD TO BLOW UP YOUR ENGINE THEREFORE YOU CANNOT AFFORD TO CUT CORNERS. The question is, How Fast can you afford to go? You wanna play ...You gotta Pay. Guys, do it right and represent your fellow MSP's. Alot of people here have Champaigne taste with beer money
 
mechanic mike said:
XoX1de, you are one of the very few on MazdaForums that actually have engine building knowledge that I have seen. You are correct in everything that you have stated in this thread. The only thing that I must add to what you have said is this. For those of you looking to cut corners due to finacial status YOU CANNOT AFFORD TO BLOW UP YOUR ENGINE THEREFORE YOU CANNOT AFFORD TO CUT CORNERS. The question is, How Fast can you afford to go? You wanna play ...You gotta Pay. Guys, do it right and represent your fellow MSP's. Alot of people here have Champaigne taste with beer money
Click to expand...

lol, he is arguing with lowpsi. im not saying he doesnt have knowledge in engine building but i know mark does (lowpsi) thats what he does for a living. anyone can build a motor but i have yet to see someone post in here that actually works at a machine shop and has balanced a straight 4 crank.
 
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I work in CNC machine shop, I'm actually on the board of directors. Lol, but we do space parts and small parts (the machine we have up and running is a 20mm machine)

I wish I knew more about motor building.
 
mechanic mike said:
XoX1de, you are one of the very few on MazdaForums that actually have engine building knowledge that I have seen. You are correct in everything that you have stated in this thread. The only thing that I must add to what you have said is this. For those of you looking to cut corners due to finacial status YOU CANNOT AFFORD TO BLOW UP YOUR ENGINE THEREFORE YOU CANNOT AFFORD TO CUT CORNERS. The question is, How Fast can you afford to go? You wanna play ...You gotta Pay. Guys, do it right and represent your fellow MSP's. Alot of people here have Champaigne taste with beer money
Click to expand...

Well said, I totally agree with you on the point of cutting corner. But I just tellin people that if they want a better spec than OEM balance precision, they can pay for it. Otherwise they can stay with OEM balance precision, and its not gonna blow up. exemple, if I want the motor rev up to 8000 I will defiinitely balance the crank precisely. If I dont want to rev higher than 6500, I dont need to balance the crank because OEM did it, I only need to scale the weight.
 
Here's what I found why our engine do have counter weight: "You CAN omit the rotating and reciprocating masses and balance a crank with no ring weights when the crank is symmetrical. An inline 4 cylinder, boxer 4, inline 6, inline 8 or a V-12 all fit the bill (along with many others). In all these engines the cylinder geometry is such that the primary shaking forces cancel out. For example, in the I-4 or boxer 4 the two outboard pistons are at 0 degrees while the two inboard are at 180. The forces are not only opposite in direction but are symmetrically distributed along the crank so cancellation occurs. No engine needs internal counterweights, but one on each end is necessary to achieve dynamic balance. The internal weights just cancel out bending forces, making the crank and bearings less subject to failure."

good reading @ http://www.steamautomobile.com/phorum5214/read.php?1,9967,9967
 
dandan2 said:
lol, he is arguing with lowpsi. im not saying he doesnt have knowledge in engine building but i know mark does (lowpsi) thats what he does for a living. anyone can build a motor but i have yet to see someone post in here that actually works at a machine shop and has balanced a straight 4 crank.
Click to expand...


Sorry I didnt include lowpsi. Maybe I should have listed all the names of those I feel that are knowledgable. I too work at a machine shop. I am a ASE Recertified Master Engine Machinist and have been working at a Performance Machine shop for over 16 years now. I'll try and be more precise in my postings/replies.
 
Also, I forgot to mention. I onced worked for a auto machine shop here in Houston and I must say the difference between an auto machine shop and a Performance Machine shop is as the titles state. In the regular auto shop we produced fast turnarounds of your average valve jobs/short block/long block stuff while at the Performance shop we specialize in Head/Intake Porting, O-ringing to the block and/or head, angle milling, knife edging to the crank, etc,etc.
 
sorry to thread jack, but with all this experience and knowledge in here, i gotta ask, im about to go forged and what valve jobs should be done to ensure proper function. dont want top performance, trying to save money but still dont want to cut corners.
 
you dont need valve job to be done, if you dont want top performance. our head design stock is plenty efficient.
 
protege321 said:
dont need to have them cleaned or re-seated? just off the block and back on?
Click to expand...

a good 5 angle valve job should restore ur head and make ur top end like new again, just like ur bottome end. its not really needed but affordable and would freshin things up.
 
you can steam clean the valve but valve job is not a MUST unless you want to improve ponnie output. Only thing I did to the head is valve carbon cleaning, new valve stem and exhaust port porting. It depends what is your ponnie goal, if says 400+ you better port the head.
 
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